THE GEODETIC NETWORK ANALYSIS, PREREQUISITES AND FACTORS OF THE NEED FOR GEODETIC MONITORING OF SETTLEMENTS AND STRUCTURES DEFORMATIONS

Abstract

The purpose of this article is to analyse the geodetic network, prerequisites and factors that arise for geodetic settlements monitoring and deformations of the ChNPP engineering structures. It is determined that one of modern applied geodesy directions is deformation monitoring. It consists in regular monitoring of buildings deformations and other important structures by geodetic methods, carried out with the aim of timely detection and prevention of emergency situations. The factors influencing the emergence of new tasks and changes in the construction situation at the shelter facility, which necessitated the reconstruction of the planned and height geodetic network, are analysed. The necessity of organising observations of new control marks in the western part of the shelter is established. The influence of external factors that cause structural changes to the foundation under the building, the outer parts of the brick walls and man-made factors, the mechanism and intensity of these processes were analysed. The optimum height of sedimentary marks from the level of the blind area is determined. The list of objects for monitoring and observation of the building structures of the shelter was determined. The scheme of the main planned reference geodetic network at the facility and ensuring the required accuracy of deformation measurements was developed. The long-term control leveling of the height network of the investigated object shows that its reps, especially the deep and fundamental ones, are stable and can be used for further observations of vertical structures deformations. Thus, to ensure proper accuracy of leveling control marks of buildings and structures of the shelter complex, the height network of deep and fundamental references should be such that the distance between them does not exceed 0.5 km. The tolerance for the accuracy of subsidence determination of the marks of the upper shelter levels, which can be determined only by remote method, for example, trigonometric leveling, should be taken as for the II class of measurement accuracy, not more than 2 mm.